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AUTHOR'S EDITION. 



REPORT 



UPON THE 



INSECTS OF TIIK SEASON IN IOWA. 



HKRP>EKT OSBOHN. 



[ EXTRACTED FKOM THE REPORT OF THE ENTOMOLOGIST, ANNUAL 
REPORT U. S. DEPARTMENT OF AGRICULTURE FOR 1887.] 



ATJTHOR'S EDITION. 



REPORT 



UPON THE 



INSECTS OF THE SEASON IN IOWA. 



HERBERT OSBORN, 



[EXTRACTED FROM THE REPORT OF THE ENTOMOLOGIST, ANNUAL 
REPORT U. S. DEPARTMENT OF AGRICULTURE FOR 1887.] 






REPORT UPON THE IXSECTS OF THE SEASON IN IOWA. 

By Prof. Herbert Osborn, Special Agent. 

Ames, Iowa, November 30, 1887. 
Sir : I herewith transmit to you my report of observations for the summer of 
1887. I desire to express my thanks to you and your assistants for the determina- 
tion of doubtful specimens, and for the many other favors which you have been so 
ready to grant. 

Respectfully, 

Herbert Osboen. 
Prof. C. V. Riley, 

U. S. Entomologist. 



THE TURF WEB-WORM OR SOD-WORM. 

(Crambus exsiccatus, Zeller, var.) 

My attention was first called to this insect, wliich has proven a most serious pest 
the present season, by a note from Mr. Henry Barnes, who owns a farm near Gil- 
bert, Story County. Under date of May 34 he writes: 

Dear Sir : Inclosed I send you bottle, in which are some specimens of a worm 
tliat is making sad havoc with our sod-corn. They eat the stalk off beneath the 
surface and many of the leaves are punctured full of holes. In some ]iarts of the 
field nearly every hill is infested with the " varmints." Can you tell us how long 
the}' are likely to continue their depredations, so we can tell whether it will pay us to 
replant ? The land from which the specimens were taken was seeded down some 
eight years since, and was mainly blue grass and white clover. Has been used for 
a sheep pasture about six years. Was underdrained and broken up last fall and this 
spring, and planted to corn with the above result. Will be greatly obliged for any 
information you can give us on the subject, and shoidd be pleased to hear from you 
as soon as you can make it convenient, so that in case you can suggest anything 
likely to relieve us of the pest or enable us to escape his work we may have time to 
avail ourselves of the knowledge. 
Yours, respectfully, 

Henry Barnes. 

In reply I recommended replanting and stated briefly the probable history of the 
insect. This reply was published in the State Register, and shortly after the fol- 
lowing letter was received: 

OssiAN, Iowa, June 9, 1887. 

Sir : I have seen your answer to Mr. Barnes in the State Register of June 3. Now, 
my corn has been destroyed in precisely the same way. It was planted on the 8th 



3y Trauarof . 



KEPOllT OF THE ENTOMOLOGIST. 155 

of May, and came up immediately and looked very nice, but it was taken in about 
two days, so that the field looked perfectly bare. We re| lanted on May 21. The 
corn came up very nic again; we have harrowed it and plowed once, but there 
will not be a hill in (he field to-morrow night that will not be jjartially or wholly 
destroyed. This certamly can not be the same woi'm that is troubhng Mr. Barnes, 
as they have been in n\y corn for three weeks, and I can not see any change in 
their appearance. As it is now too late to try corn again would it be safe to sow 
corn for fodder? The hay crop in this (Winneshiek) county is a failure, and this 
piece of ground has got to pi'oduce something. It was seeded to timothy and clover 
three years ago and has been used for hog pasture since that time. Inclosed find 
bottle containing specimens. Will be slioi't of feed next winter and any advice or 
suggestion will be thankfully I'eceived. 
Respectfully, 

A. W. OXLEY. 

To this I replied advising to put in corn and stating my belief that the adults 
were already issuing from the chrysalis state.* 

Early in June I had noticed the strijied ground-squirrels on the college lawn dig- 
ging into the turf and eating something which they Avithdrew. Examining the 
places thus dug up I alwaj's found the peculiar cocoon of a Crainbus, and the place 
would also show tho deserted web and burrow of the larva. These squirrels' bur- 
rows were very numerous in some i^arts of the lawn, and in one place I counted 
twenty-five in the space of a square yard, indicating tliat the ground-squirrel has dis- 
posed of that many larvae or pupse of Crambus within the given area. At another 
time I counted fifty to a square yard. Evidently when sod -worms are plenty the 
ground-squirrel is not an unmixed evil. 

I did not at first connect these worms with the ones referred to by Mr. Bnrnes, 
but comparisons of specimens of larvae found in sod here with the imperfect speci- 
mens sent by Mr. Barnes, and later with those from Mr. Oxley, satisfied me that 
they were very probably identical. Svibsequent observations made this almost a 
certainty. I have therefore dealt with them as belonging to the same species. 

E vidently we must consider it under the double role of a gi-ass pest and a corn 
pest, and while it certainly causes in the aggregate vastly more damage to grass 
than to corn its work is more noticeable on the latter crop, since it so completely 
destroys fields planted upon sod infested by the young worms. 

Since this insect has assumed so great an importance to two staple crops, and as 
its life history and habits have been but partially recorded, I have devoted as much 
time as possible to a study of it the present season and will give the result of my 
studies in detail. 

Its distribution and injury so far as the corn crop is concerned may be gleaned in 
part from the Iowa crop report, which has kindly been placed at my disposal by the 
secretary of the State Agricultural Society, Hon. J. R. Shaffer. Aside from the 
localities given in the following list there was considerable damage in this (Story) 
county, and, as stated by Mr. Oxley, in Winneshiek County. 

Extracts from crop report. 

Bremer Cotjnty. — Corn on old ground injured by a small green Avorm. 

Clinton County. — Cut-worms injured coi-n on timothj' sod and old pastures. 

Davis County. — Corn on sod and fallow ground has been destroyed by Web- 
woi'ms. 

Fayette County. — Corn looking well, notwithstanding the severe drought; 
some planted on timothy sod injured by Cut-worms, but general stand good. 

Henry County. — Meadow- worms working at the roots of grass. 

Van Buren County. — A worm resembling the Cut-worm has done serious dam- 
age to corn; it built a web in the hill and would eat whole fields planted on new 
ground. 

Johnson County. — Cut-wox-ms destroyed 25 per cent, of the corn planted on sod. 

Jones County. — Corn two weeks ahead of last year. That replanted on account 
of Cut-worms is gaining on the other. 

* In answer to further inquiries as to results in these fields Mr. Barnes informs 
me that the replanted corn was not materially injured by the worms, and that 
taking drought and Chinch Bugs into account produced a very fair crop. He 
further says that the portion of his field most damaged was the part plowed in 
spring. Mr. Oxley states that the worms took three plantings for him, but that he 
then planted to fodder-corn and raised a most excellent crop; he says worms worked 
in this a Little at first, he thinks as late as June 27, but did no serious damage. 



156 REPORT OF THE COMMISSIONER OF AGRICULTURE. 

Poweshiek County. — Cut-worms are doing some damage to corn. 

Warren County. — Corn somewhat injured by grub and Cut-worms, but as a 
whole prospects were never better for a good crop. 

Appanoose County. — Some sod worms; no material damage from them as yet. 

Cedar County. — Corn injured by Cut- worms, on sod grovmd much had to be re- 
planted. 

Clark County. — Corn damaged by Cut- worms. 

Davis County. — Corn on sod taken by Cut- worms ; many replanting the third 
time. 

Delaware County. — Some timothy fields entirely destroyed by Cut- worms ; 
many being plowed up and planted to corn. 

Jefferson County. — Corn on old ground good, but is being destroyed by Cut- 
worms on timothy sod; much has been replanted. 

Johnson County. — Corn a good stand, except that on timothy sod has been cut 
off by worms. 

Keokuk County. — Corn planted on sod injured by Cut-worms and much had to 
be replanted. 

Lee County. — Corn generally good and forward for the season. New Web 
Wire- worm cut off most of the corn planted on sod plowed this spring. 

Pottawattamie County — Cut-worms and ground moles doing some damage 
to corn, but generally it is a good stand and color. 

Van Buren County. — Corn planted on timothy sod being replanted the third 
time, Cut- worms taking all corn planted on sod ground. 

Wapello County. — Corn on sod ground had to be replanted * 

The extent of its ravages in meadows in other parts of the State I am unable to 
give with any precision. On the cc^llege farm, both on the campvis and in the pas- 
tures and meadows, it has been very abundant and the gi-ass ha=? suffered seriously. 
In patches the damage was such that it has not recovered, while over large areas 
the grass being cut off above the crown has grown up rapidly since the fall rains. 
During the severe drought, which extended till the 1st of September, the damaged 
portions did not show plainly, as the whole surface was dried up, but after the rains 
such areas were much slower in becoming green. But that the damage was not 
due to dryness was evidenced by the greatest damage occurring in depressions or in 
places where there was tlie most moisture, instead of on the tops of the knolls or 
in specially dry places. On the line of the Northwestern Road from Ames to Clinton 
I saw in ^the" latter part of August many meadows and pastures presenting the 
whitened patches indicative of the presence of this pest. Outside the State, in 
Illinois and Wisconsin, I found evidence of it wherever I went. 

The insect is distributed widely over the country, and I doubt not has been de- 
structive in all the Upper Mississippi Valley, though probably a large portion of the 
damage done by it has been ascribed to the drought or other caiises. 

The injury to corn results only from planting upon sod. As it is very desirable to 
make this transfer when the meadows have been severely injured it becomes of the 
utmost importance to the corn crop to avoid the damage done, which necessitates 
replanting and causes vexatious delay. The measures necessary to avoid this dam- 
age I believe to be simple and practicable, and they will be fully stated under the 
head of remedial measures. 

Habits and life history. — Owing to the abundance of this species upon the col- 
lege lawn I have had ojjportunity to observe it during the entire season in all stages, 
and though some points of interest remain to be studied, I am able to state the 
principal facts in regard to its life history. Enough I am confident has been deter- 
mined to form a solid basis for recommendation of remedial measures. 

During the last of May and fore part of June larva? and pupje were abundant, 
and were observed as late as June 10. On June 7 the moths were plenty, and June 
9 tliey were flying to lights in the iKuises by thousands. They came to my study 
in swarms, and I was afterwards told by students that they gathered to the electric 
lights in the college building in such numbers as to seriously interfere with their 
work. On the morning of the 10th, having closed the windows of my study the 
night before to jirevent the moths from escaping, I counted over one hundred 
moths at one window, and the window-sill, the sash, and the floor in front of the 
window were thickly strewed with tlieir eggs. On slightly pressing the abdomen 
of a female with thumb and finger she e.\,truded, one by one, thirty-five eggs, after 
which none were extruded by pressure, but 'upon dissection of the moth I found 
ninet)" well-formed ova and a large but uncertain number of formative stage in 
tubes of the ovary. As this was a captm-ed female and she had had time during 

*I have included in the above extracts those given as Cut- worms, etc., though 
some of these very likely may refer to other species than C. exsiccatus. 



EErORT OF THE ENTOMOLOGIST. 157 

the night to dispose of eggs which I did not count, I could not determine the full 
number possible from a single individual, but from those counted and those par- 
tially formed in the ovary it seems perfectly safe to say that each female can deposit 
at least two hundred eggs. The eggs are yellowish-white, oval in shape, with usu- 
ally fifteen longitudinal ridges. In a few instances I noticed more. When extruded 
they are held momentarily at the tip of the abdomen, giving them time to dry, so 
they do not adliere to any object upon which they drop, but before the extrusion 
of another egg are snapped sharply away by a contraction of the Ups of the vulva, 
wliich appears to be armed with a row of minute bristles. Eggs in tliis way were 
thrown quite a distance, and when being deposited in grass would be sent well 
down among the dead leaves at the surface of the sod. In a few cases I noticed 
one egg remain till the next was extruded, and the two would adhere slightly, but 
doubtless the natural extrusion is not so rapid as that induced by pressure. 

On June 11 the moths still shut up in my room had deposited eggs in greater num- 
bers than the night before, and some of them confined in a glass jar had also depos- 
ited many. 

The eggs collected on June 10 hatchetl on June 18, and I infer that fertilization of 
the females had taken place previous to their flymg to hght. A point which I did 
not carefully determine is the proportion of males to females in those gathering to 
lights, but my impression is that the females were largely in excess. 

Some of these newly -hatched larva? were placed in a jar with earth and fresh grass, 
others in a jar without earth, while still others were scattered over a small area 
of grass out of doors in a place convenient for observation. These last could not 
afterward be found at all and the grass showed no signs of their presence. Being in 
a very dry location and the grass becoming badly dried up I suspect they did not ob- 
tain sufScient moist food to enable them to start then- gi'owth. The young larvae 
when supplied with fresh grass collected at the broken ends and fed with avidity. 
Their bodies, at first pale, became after feeding yellowish-green, the liead and upper 
part of the first segment being black. On the 20th I noticed that one of the larvae had 
formed a tube by drawing together the edges of a blade of grass, while still 
otliers had gone under the earth at bottom of jar. Unfortunately, duties that could 
not be postponed prevented attention to these larvae and a few days later they were 
all dead. One, however, had formed a basket-work attaclied to blades of gi'ass. 
This had probably been formed as e;irly as June 25. By the middle of July the 
larva? were becoming conspicuous by tlieir ravages in corn, and subsequent obser- 
vations were made either directly in the field or upon larvae collected and confined. 
Notes for July 13 and 16 record larva? numerous in part of one field of sod-corn 
confined to a portion of the field last plowed. As the time of plowing aj^peared to 
be an important item I obtained, through the kindness of Mr. F. S. Schoenleber, the 
exact dates of plowing of the fields planted to sod-corn. One field plowed 9th to 
11th of May contained no turf web- worms and no signs of their Avork. Another 
field had been plowed in part May 12, VS, 15, and 18. The remaining central por- 
tion was jDlowed on the 7th and 8th of June. The portion first plowed was entu'ely 
free from injury by worms, while the part last plowed was badly infested. The line 
of separation between that first plowed and that last plowed was in some places dis- 
tinctly mdicated by the missing hills or damaged stalks, indicating the presence of 
worms. It seems reasonably certain, therefore, that Crambus eggs were deposited 
on the central part in the grass before the sod was turned June 7 and 8, and the 
larvae hatching by the 15th to 18th of the month had no other resource than to attack 
the corn which came on shortly after. As already stated, Cra;mbus adults were 
abundant June 7, and had doubtless been present in fewer numbers for several 
days, so there was opportunity for the eggs to be deposited on the grass land prior 
to the plowing June 7 and 8; while from the absence of worms in tlie other sod- 
corn it was evident that no eggs were laid on the gi-ound plowed previous to the 
first of June. None have, with possibly one or two reported exceptions, ever been 
found in corn-fields except when planted on sod. The exceptions, if referring to 
this species, may probably be accounted for in other ways than by assuming eggs 
to be laid on ploAved land. 

In corn the young worms construct a web from half an inch to an inch below 
the surface of the ground, usually winding it irregularly among the roots and 
stalks of corn. Frequently a number of these worms occur in a single hill, but as 
a general rule only one or two are found well developed. Hills infested by these 
worms have the stalks when small cut i^artially or entirely off, sometimes, I judge, 
the upper portion being entirely devoured. Larger stalks have cavities gouged out 
of tlie sides at the surface of the ground and a little above. The leaves also are 
eaten at base and numerous holes scattered over the blade. Sometimes these holes 
are arranged with a peculiar regularity, occurring in transverse rows three to five 
holes in each row, and the rows about the length of the worm apart. The stalks at 



158 EEPORT OF THE COMMISSIONER OF AGRICULTURE. 

the surface of tlie ground are sometimes blackened and decayed, and in some in- 
stances I tliought I detected tlieir work on the roots. Naturally they do not find 
food in sucli abundance as in grass and maj' be expected to take whatever they can 
most readily attack. 

On July 20 larvae were found in corn apparently full grown and ready to pupate. 
Specimens confined in a glass jar with a little earth maturetl, two adults issuing and 
'first noticed Augusts, both fresh and apparently but recently expanded. Larvae 
were found in corn as late as August 9, and from these I had one advilt issuing during 
my absence and first seen by Professor Hitchcock August 25. 

In Lrass land the larvte form a web-lined burrow about half an inch beneath the 
surface of the sod. extending as the larva grows to a distance of 4 or 5 inches, 
nearly straight, and opening at the surface of the sod. The grass above and sur- 
I rounding these burrows is cut off just at the surface of the ground ; and where the 
worms are plentj' the grass cut off forms a complete mat, which can be drawn 
aside, exposing the burrows of the larva?. By jtushingup the sod along the burrow 
the web and worm are brought to A'iew. The roots and usually the crown of the 
plants, except directly above the burrow, are unaffected, though from the failure of 
some patches to revive even six weeks after rains have entirely restored other parts 
of the lawn it would seem that in some spots the worms were so hard pressed for 
food as to eat down into the crown. August 4, and for a number of daj^s there- 
after, full-grown worms forming cocoons could be found in abundance, and gradually 
adults became more numerous, till in the middle part of August and until the fore 
part of September they were again aliundant. They were swarming to lights 
August 11. From this on the adult decreased in number, and the last record I 
have of seeing them is October 3. 

This is as far as I have made positive observations on the species, but it is proba- 
bly safe to infer that the eggs laid in the fall hatch and the young larvae establish 
themselves in burrows where they pass the winter and awake to resume feeding in 
the spring. By the latter part of May the bulk of this brood is full gi-own, and, as 
we have seen, the moths issue in swarms between the 7th and 20th of June. 

The insect is double-brooded, though scattering moths may be seen as late as last 
of June for the spring brood and as early as first of August and late as fore part of 
October for the fall brood. 

The life history, as I have observed it and supplying by inference the winter con- 
dition of one brood, may be summarized as follows : 

Moths of the spring brood appear in June; early stragglers by the 1st. the bulk of 
the brood from the 7th to the 15th, and late stragglers till the 1st of July. These 
deposit eggs ^vhich hatch in eight days from time of deposition. The larvte require 
fi"om five to seven weeks to become full-grown, forming in the meantime a web- 
lined burrow in the sod, within a portion of which or in sod close by they form a 
cocoon and change to the pupa stage. The pupa stage is passed in from twehe to 
fifteen daj's, the fall brood of moths appearing in August, early sti'agglers the 1st 
of the month, the bulk of the brood during the middle of the month and till the 1st 
of September, and late stragglers are seen till fore part of October. Moths of this 
brood dei^osit eggs for the fall and winter brood of larvae, which larvge mature by 
the latter part of May, pupating during last of May and fore part of June. These pro- 
duce the spring brood of moths which appears in early June and the cycle is complete. 

Description of different stages. — Reference has already been made to tha appear- 
ance of different stages, and technical descriptions of some of the stages in other 
publications makes 'it unnecessary to go into detail here. I may state in brief, how- 
ever, the most striking characters, in order that the insect may be recognized by 
those interested. It may be said, however, that it so closely resembles other species 
of the same genus that except to the professional entomologist a separation is next 
to impossible. Differences in habit, however, will assist in distinguishing them. 

The egg is .55""" long and .30""" in diameter. It is fluted or ribbed longitudi- 
nally, the ribs numbering usually 15, rarely 16 or more. They are yellowish white, 
becoming darker as they reach the time for hatching. 

The larva when newly hatched is .70""" to .75""" in length. The body is pale, 
almost white, while the head and upper part of the first segment is dark brown or 
blackish. The body is provided with scattering fine hairs. When full-grown it is 
nine-tenths of an inch long when extended, of a light brownish color, the head and 
tipper part of first segment darker, and the head blotched with blackish. The seg- 
ments following the fii'st have glassy, slightly elevated, darker spots, from which 
arise fine hairs. 

The pupa is bright reddish brown, half an inch in length, the terminal part obtuse 
and blackish. It is inclosed in an elongate oval cocoon made of a thin web and 
covered with green frass. which looks? much like bits of grass cut fine, and indeed 
they seem to be but partially digested. A cocoon formed in a glass jar from corn 



REPORT OF THE ENTOMOLOGIST. 159 

leaves seemed to be cut and used entirely undigested, and I surmise tlie matc>rial is 
cut especially for this purpose and passes directly througii the body, to be used on 
the cocoon. 

The moth is of a light ashy color, and fresh specimens show two obscure oblique 
dark stripes passing from tlie hind border toward the apex on the front wings. The 
wings are folded closely ai'ound the body when at rest. The length of the body is 
about one-half inch, and the wings expand an inch and one-eighth to an inch and 
one-fourth. 

Remedies. — Under this head we must treat separately the measures to be adoptetl 
for corn and meadows or pastures. 

As corn is attacked only when planted on sod, the damage being done by larvaj 
hatching from eggs deposited in grass or by larvae that have partly obtained their 
growth in grass, all methods of prevention should recognize the time at which eggs 
are deposited and the larvas mature. 

When the worms are already at work in the corn the cheapest and best method 
is probably to rejjlant, for the larvas must all or nearly all mature by the middle 
of June at latest, and then no further damage need be feared. Reports show that 
this practice was successful, thougli in many cases fields were planted the third 
time. It would be well in planting on sod ])lowed late in the fall before to delay 
planting as long as practicable, thus starving out the majority, at any rate, of the 
worms, and then, if necessary, replanting as soon as possible when hills show pres- 
ence of worms. If possible, however, the plowing; should be done early in the fall, 
so as to prevent the eggs being deposited, or if deposited to starve out the larvee 
before they have prepared for their winter fast. To be most effectual the plowing 
should be done before the 1st of September, and if the land be meadow land not 
used for fall pasture it will be safest to plow as soon as possible after the crop is 
off. When the sod is to be plowed up in spring it should l)e deferred if worms are 
present till they begin to change to pupae, or for this latitude till the middle of 
May, and should be done before the moths make their appearance, or by the 1st of 
June. Our notes show that here sod plowed in May remained entirely free from 
worms, while that plowed the second week in June, just after appearance of moths, 
was badly infested. If noticed when they first begin their work on corn it is prob- 
able that the use of bisulphide of carlion would effectually destroy them, but it is 
doubtful whether it would be as satisfactory as replanting. The worms are easily 
detected, since they are to be found in their webs in the day-time, and they can be 
picked out by hand quite rapidly, as I know from experience. Possibly boys could 
be employed to collect them with good profit. These methods should be resorted to 
only in cases where preventive measures have not been employed. But in this case 
prevention is so easy that there seems little need of trouble from the pest when its 
habits are understood. 

In meadows badly infested and thereby run out one method to be adt)pted, where 
circumstances will permit, is to plow up the sod and plant to another crop ; but to 
avoid damage to the new crop, especially corn, the sod should be turned before the 
1st of June, if in the sj^ring. and if in fall before the 1st of September. If, how- 
ever, the plowing is done prior to the egg-laying either of spring or fall the moths 
"will fly to such pastures and meadows as are left and concentrate there, thus causmg 
greater damage. On this account some plan should be adopted to prevent, if pos- 
sible, that source of damage. If the land can lie after plowing to starve the worms 
it will be a good plan to defer jjlowing till eggs are laid and then turn them under 
to starve. In fact, knowing the cycle of life in the insect, and the time at which 
eggs are laid and the worms hatch and mature, each cultivator can adapt his 
measures to the special circumstances of his particular field. 

A plan by which to greatly lessen the number of moths and the injury resulting 
from their presence in meadows and pastures may be based upon their habit of 
congregating in such immense numbers to light. I have shown that the moths 
thus attracted are in large part at least the females loided with eggs, audit is 
probable that they have deposited few egis if any previous to their flying to the 
light. Hence every female moth captured means the destruction of from one to 
two hundred eggs at the least. As the moths come to light by thousands, I think I 
may say even by millions, within a square mile, it can be seen how important is 
their destruction. Hundreds of them perish as a result of their own self -destructive 
haljit, but by taking advantage of this habit and placing lanterns over tubs or pans 
of water in exposed places where they may be seen considerable distances, hosts of 
moths may be captured and destroyed. A little kerosene on the water will make 
their destruction certain, as then, even if they succeed in crawling out over those 
already submerged, or at the sides of the tub, tliey are quite sure to have received 
enough oiling to kill them in a short time. A little care in killing those accumu- 
lating in houses will also assist in lessening their number. Where electric lights 



160 BEPORT OF THE COM:MISSIO]SrER OF AGRICULTURE. 

are in use they may be utilized to especial advantage in the capture of thousands 
of moths. I see no feasible plan of attacking the larvae after they are established 
in the turf. 

Natural enemies. — I have already mentioned the fact that the pupae, possibly the 
full-grown larvae, are extensively preyed upon by the striped squirrel {SpermopM- 
lus 13-lineatits). Unfortunately this sprightly little rodent has a taste for other 
food, which has gained for it a very unsavory reputation as a farm adjunct. Doubt- 
less where corn is cultivated the injury to that crop will overbalance the good they 
may do in meadows; but I am incdned to think that for land kept constantly in 
grass their value is far greater than usually supposed. I know they feed upon, 
the seed of grass and clover and doubtless also to some extent on the leaves and 
stems, but they also feed on noxious weeds and insects. 

During several years' close observation of them on a lawn I have failed to find, 
any indication of serious damage to the turf, and could they be kept in bounds I 
should feel hke recommending that for permanent lawns they be allowed a home 
for the sake of the insects they devour. They seemed to select the cocoons of the 
turf-worms infallibly, pouncing ujton a certain spot, digging for an instant, and 
then sitting upright to devour the dainty morsel. 

Other mention of the species and related forms. — In his first annual report as State 
entomologist of New York, pp. 149. 150, Prof. J. A. Lintner gives the result of a breed- 
ing of one larva of Crambus exsiceatits in connection with a detailed account of 
the Crambus vulgivagellus, and there expresses the suspicion that the insect is- 
double-brooded. 

In the fourteenth annual report of the State entomologist of Illinois, i^p. 12-17, 
Prof. S. A. Forbes describes under the name of Crambus zeellus, Fernald, an insect 
which in many respects resembles the species here discussed. In some respects, 
however, there is considerable difference, and I have not attempted to determine 
the relationship between them. This species described by Professor Forbes is men- 
tioned and a letter relating thereto is published in Bulletin No. 12, p. 33, Division of 
Entomology, United States Department of Agriculture. 

I can not overlook the possibility that there may be more than one species in- 
cluded in the records here presented, and indeed for the reports from over the State 
there is every probability that two or more forms are included under the general 
name of sod-worms, web-worms, etc. 

The occurrence of Crambus vulgivagellus, for instance, in company with exsic- 
catus would account for several apparent discrepancies in reports concerning the 
time of pupation of the Web- worm. It has been my effort to record the facts as 
observed and reported, and the distinction of the different species, if such be included, 
must be worked out in the future. There can be no question, however, that the- 
great body of the swarm appearing here the present season belongs to one siiecies. 

THE WHEAT-HEAD ARMY-WORM. 

(Leucania albilinea, Guen.) 

An insect which can without doubt be referred to this species caused very con- 
siderable damage in some of the southeastern counties of the State. Unfortunately 
I was not aware of the damage till too late to secure specimens for determination. 
Descriptions of the larva and its work, however, are so characteristic that I feel 
confident it was this species. I subjoin extracts from the Iowa crop report for July 
10. 1887, which will show the distribution and damage so far as reported. 

It will be noticed that the area included extends from the Mississippi River to a 
little west of the middle of the State and comnrises only the two southern rows of 
counties, with the exception of Adair, which coi'ners to the northwest upon the 
last infested county in the second row. Estimates given for two of the counties: 
place the loss at 75,000 bushels (equal to about |150,000) in one (Jefferson) and at 
$30,000 in the other (Wayne). It is possible that these estimates are too high, but 
if we cut them down one-half and suppose the other eleven counties reported to- 
have suffered in like ratio it would make a total loss of over half a million dollars 
for the thirteen coimties. Doubtful counties out of this area may have suffered 
more or less, but not so consjiicuously as to attract attention. The moths were 
noted at A.mes during the summer, but not in unusual abundance. 

Extracts from loioa crop report. 

Adair County. — There is some new insect eating off timothy heads. 

Appanoose County.— Timothy heads eaten off by worms. There will not be 
any seed in Franklin Township. Witliin the last fifteen days a worm looking like 
an overgrown measuring worm made its appearance on timothy heads and com- 



KEPOET OF THE ENTOMOLOGIST. 161 

pletely stripped many pieces, damaging the crop very much ; they have disap- 
peared. Timothy light, a small green worm eating off the heads. Timothy heads 
destroyed by a small green worm. 

Clarke County. — A worm working on timothy heads. 

Davis County.— Worms are eating off timothy heads. Timothy heads eaten off 
by a peculiar green worm, name unknown. Timothy heads destroyed by a small 
green worm. 

Decatur County.— Green worms working on timothy heads. Worms have de- 
stroyed timothy heads. Green worms playing havoc with timothy heads. A worm 
has almost destroyed timothy heads. 

Des Moines County. — Timothy heads eaten off by a small green worm. 

Henry County— A light-green worm 1 inch long has done great damage to 
timothy heads. A green worm did some damage to timothy heads, but has disap- 
peared. Meadow worms M^orking at the root (of timothy) and a green worm about 
li inches long, name unknown, working on the head. Tunothy heads destroyed 
by worms. Timothy badly damaged by a small green worm eating the head. 
Timothy being cut to save it from worms. 

Jefferson County. — Some worm working on timothy heads, stripping off chaff 
and seed and leaving stems naked. Timothy seed, of which this county usually 
ships about 75,000 bushels, will not exceed the wants of home consumption. 

Lee County.— Timothy injured by a small worm eating off heads. A small 
green worm has done great damage to timothy heads and is working on oats. 
Timothy heads destroyed by worms. 

Lucas County. — A green worm has appeared on timothy heads and will ma- 
terially lessen the seed crop. Bountiful rains June 10 to 18 promoted growth of 
timothy 10 per cent. ; a worm from half to two inches long appeared about the 
same time and has devoured whole fields. They do their work principally at night. 
Timothy seed has been completely destroyed by myriads of green worms. A worm 
doing damage to timothy heads. A small green worm doing great damage to 
timothy heads. 

Ringgold County. — Timothy will be a short crop in many fields; heads of timo- 
thy entirely eaten off by a green measuring worm. Grasshoppers and worms head- 
ing timothy; small green worm eating off timothy heads. 

Van Buren County. — Timothy heads eaten off by worms. "Army- worms" are 
destroying timothy meadows. Timothy damaged by drought and a small green 
worm working on heads. 

Wayne County. — A worm, name unknown, cutting off timothy heads. Sod (of 
timothy) injured by spring drought and latterly a worm eating off the heads. There 
is a small green worm doing much damage to timothy heads. A worm three-quar- 
ters inch long is eating the timothy; wnll not be more than 10 per cent, of a crop, a 
loss of $30,000 to this county. Timothy heads destroyed by worm; timothy heads 
eaten by worms. A worm resembling a Cabbage-worm is destroying timothy heads. 
A small green worm eating timothy heads. 

blister beetles. 
(Lytta cinerea and Epiccmta tnttata.) 

Two species of these common beetles were unusually abundant this season, doing 
considerable damage to various plants, and in a number of instances causing quite 
serious blistering upon the faces and hands of people. I noticed an item in the daily 
paper to the effect that in a certain town in Missouri they were so plenty, flying into 
houses by night and producing such severe blisters, that people were obliged to 
avoid lighting lamps in the evening. Several of the college students suffered from 
blistered faces after handling the cinerea, and I was myself adorned for several days 
with a swollen face, having, as often before, gathered a number in my hand and 
probably while perspu-ing brushed some j^art against my face. 

Lytta cinerea was the species first noted as abundant. June 7 and 8 it was plenty 
and stripping leaves of Honey Locust. June 9 I observed some of the beetles feed- 
ing upon clover, and that evening noted it attracted to my hght. Specimens were re- 
ceived from Hancock County, where it was reported destructive, and it was also 
reported destructive to potatoes in Cerro Gordo County. 

Tlie Striped Blister beetle {Epicauta vittata) damaged some of the potato patches 
in and about Ames, and July 20 I noticed them plenty on injured corn, but as grass- 
hoppers were present they may not have caused the damage. The following items 
from the crop report apply, most of them certainly, to this species, while some may 
apply to either this or the preceding species: 

Adams County. — A long striped bug is eating potato vines. 



162 REPOKT OF THE COMMISSIONER OF AGRICULTURE, 

Clarke County. — Potatoes damaged by a long striped bug. 

Clinton County. — Flying potato-bugs threaten late potatoes. The Spanish Fly 
is very destinictive to the potato crop. 

Henry County. — Potatoes have been badly eaten by the long striped bug. 

Jackson County. — A new species of potato-bug has appeared, but as yet no dam- 
age done. 

Johnson County. — We have Colorado and two kinds of long bug. the latter 
headed off by Paris gi'een. Army bugs are very bad on potatoes and corn. Colo- 
rado beetles appeared in small numbers and needed no attention, but the flying 
variety are extremely numerous and doing gi-eat damage to potato crop. 

Montgomery County. — A new variety of potato-bugs has appeared, doing great 
damage. They made their appearance June 8, and are equally destructive as the 
Colorado and far more difficult to destroy. 

JMany complaints have come to me that these Blister Beetles can not be killed 
with Paris green or London purple. This, I think, must be due to the insects travel- 
ing about so much, and thus leaving places that have been poisoned for their benefit. 
If care is taken to spray the Avhole patch, and especially parts not invaded by the 
pest, the result would, I think, be much more satisfactory. It should be remembered, 
too, that especially with London purple effects are not to be noted for from twenty- 
four to forty-eight hours after application. It should of course be remembered 
that in the larval stage these insects are beneficial, so that where they become de- 
structive to some valuable crop, should they be destroyed ? 

the false chinch-bug. 

{Nysius angustatus, Uhler.) 

The life history of this species, so far as I can find and as I have been informed 
by Professor Riley, who desired especial observations on the unknown points, has 
never been fully stated in that no record of the eggs or their place o£ deposition has 
been published. 

As the species has been quite abundant here I undertook to determine this point, 
and in July, when adults were plenty and copulating, I made careful search in the 
ground around roots and among the leaves and blossoms of the common trailing 
Amaranth {Amaran tus blitoides) where the insects were most abundant. My search 
was rewarded July 19 by the finding among blossoms of an egg which seemed reason- 
ably certain to be the one sought, and careful conqjarison with eggs dissected from 
gravid females proved them to be identical. 

The egg is slender, cylindrical, yellow, irregularly wrinkled, and tapering slightly 
at both ends. The smaller end is orange red. Evidently this is the head end and 
the orange-red color due to the eyes in process of formation. In eggs from dissected 
females this color is more diffused and less cons]:)icuous. While eggs may doubtless 
be ileposited elsewhere than upon the Amaranth this may Avith certainty be stated 
as one of the places of deposition, and in this locality this weed appears to be the 
chief food plant of the species. The cases recorded by Professor Riley, however 
(Mo. Kept., V, pp. 111-113), show that it may at times prove a serious pest. Where 
their destruction is desired it is evident that collecting and destroying the Ajnaranth 
during and after the time of egg deposition would be a preventive measure easy to 
apply. 

A few pupae and numerous adults, some of them copulating, were observed No- 
vember 15. Probably these adults winter over to deposit eggs in the spring. I have 
not, however, seen the adult in the early spring. As the spring brood does not ma- 
ture till July, and as observations have ifailed to show any brood maturing between 
this and late in fall we may consider that for this locality only two broods are 
produced annually. 

On July 14 (evening) I took a number of examples and noted many others that 
had flown to lights in my house, passing through the mosquito netting that covered 
the windows. 

notes on miscellaneous insects. 

Crepidodera helxines was qmte abundant in May and caused considerable damage 
to the leaves of Poplar and Laui-el-leaf Willow. Disoni/cha abhreviata was found 
upon seedling plants of Eleagnus, and I was informed that it was seen eating the 
leaves. The plants were considerably damaged and no other insect likely to do the 
damage was present. None were seen after May 20, and no further damage to 
the plants was observed. Haltiea chalyhea was observed here for tlie first time on 
grapes. Adults were seen May 18 and larvae appeared in June, but no serious dam- 
age resulted here. Farther south in the State they caused serious injury. 



KEPORT OF THE ENTOMOLOGIST. 163 

Anomcea latidavia was abundant and (June 9) observed stripping leaves of Honey 
Locust. It fed particularly upon the young leaves on sprouts. Many were noticed 
in coitu, the male with antennae kept fully extended, and body of male nearly at 
right angles to that of female. No eggs were found, and none were de^sosited by 
beetles in confuiement, but those dissected from female were .65 to .70'"" long, .40'"'" 
wide, oval, some slightly reniform, yellow, and smooth. Twenty -two were taken 
from one female. 

Phyllotreta vittata quite abundant and injurious to cabbages. They were ob- 
served (June 28) very i)lenty on leaves above and below, and one plant M-as badly 
injured by their attacks on the stem just above gi'ound. They were also quite plenty 
on Horse-radish leaves. 

Diachus auratus was found (June 29) eating the blossoms of Red Clover and de- 
positing its eggs in the clover heads. The egg is oval, light brown, and covered 
with minute irregular projections and short, spiny protuberances. The egg before 
extrusion is smooth, but wliile passing out is coated with a glutinous substance 
which hardens 9,nd forms the spiny coat. This coat is started upon the end first 
extruded, and the egg, during extrusion, is gradually rotated by means of the hind 
legs. This, I take it, is to bring each part of the surface imder the openings of the 
glands secreting the glutinous substance. Looked at from the direction of the in- 
sect's abdomen the rotation was in same direction as hands of a watch, for those 
I observed. Eggs kept in a glass tube (inclosed June 29) were found hatched the 
morning of July 13. Some of the larvae had crawled from theu- egg cases ; others 
were witlim, except head and legs, and drawing case about with them. Larvae have 
the head reddish and the body and legs white. I attempted to feed these on fresh 
clover heads, but did not succeed. 

Alydus eurinus has become quite abundant during past two or three years and 
occurs quite commonly upon Red Clover. July 21 I watched one closely for some 
time to see if it fed upon the clover, being careful not to disturb it, as they fly very 
quickly on approach of danger. It could be seen inserting its beak occasionally, 
then gi'adually withdrawing it, and to all appearance feeding. Examination of 
the clover head showed no insects, except a few larvae of Phcelothrips nigra and 
one larva of Anthocoris insidiosus, none of which showed any signs of injury. The 
Alydus could not have been feeding upon them. The habits of allied species would 
favor the vegetable diet, and I believe it may be added to the long list of clover pests. 

Anthocoris insidiosus, a well-known species, has heretofore been credited with 
preying upon certain noxious insects, and this summer, finding them plenty in 
•clover-heads with Phloeothrips nigra, I tested its relation to this species by placing 
(June 29) one of the pupae in a glass tube with a number of adults and larvae of the 
latter species. In a very few minutes it had red larva impaled and quickly sucked out 
the liquid contents of its body, so that it was shrunken to simply a head, terminal 
segment, and legs. On June 30 I placed an adult A. insidiosus in tube with clover 
plant-lice of different sizes and with adult Phloeothrips nigra. It made no attack 
upon the other insects at the time, and on July 1 had not eaten any that I could 
determine. Some of the plant-lice had molted, and this I concluded would account 
for all shininken skins present. On July 2 the ijlant-lice were all dead, only 
shrunken skins remaining, while the Anthocoris was still active. It seems probable 
that the plant-lice were eaten by the bug, since being supplied with fresh food they 
might be expected to survive more than forty-eight hours. I also saw the Antho- 
■coins inserting beak into tissues of fresh clover blossom. It did not attack the 
adult thrips. 

Piesma cinerea. — The Ash-grey Leaf -bug occurred the past summer in gi-eat 
numbers, but was not observed as abundant on any but noxious plants. A 
very few were noticed in spring on Grape but no damage to be seen. The same 
may be said of their occurrence on Plum. July 1 they were noticed in gi-eat 
numbers on Amararitus retroflexus (Pigweed or Amaranth), mostly paired, and on the 
Tinder surface of leaves were numerous eggs, which I took to be of this species. 
This I proved by confining adults and securing eggs, and further by watching de- 
velopment of larvae. A very few young larvae were also noted at tliis time. The 
eggs are yellow, elongate, shghtly bent, with about ten longitudinal ribs, the head 
end cut square off, and the red eyes showing plainly in eggs nearly ready to hatch. 
The larvas when first hatched are two-thirds of a millimeter in length and a fourth 
of a millimeter in Avidth, the antennae four-jointed, the eyes red, and a red spot 
showing very plainly in the abdomen. By July 12 many larvae on the plants ob- 
served were over half -grown, being at this time green in color. July 19 all stages 
were abundant, but many in pupa stage and many adults apparently fresh from 
the pupa stage with the wings delicate, almost white, and the body throughout 
green, except the red eyes. Two pairs apparently recently-issued adults were 
noticed iti coitu. The green color is evidently retained for some time after reach- 



164 REPORT OF THE COMMISSIOKER OF AGRICULTURE. 

ing the adult stage. This species was also observed, though less abundant on 
Amaravtiisblitoides, , , ^ rm • ^ -i- • 

Ervthroneura vitis was abundant throughout the season, as also Tlirips tntici, 
anil Fhlceothrips nigra was present in immense numbers m clover blossoms, both as 
larva; and adults, and I think there can be no question but that they get their 
nourishment from tlie plant. There seems, however, to be no very decided mjiuy 
as a result of their presence, though it is to be noted that many clover lieads where 
thev are present blacken early and do not set seed apparently as full as they should. 
I have seen adults of the latter species working their jaws rapidly on the tissues of 
clover blossoms, but could not discover any of the tissue bitten awav. 

Tetranychus telarius.— In adtUtion to the usual plants mfested bythis mite I 
have observed it this season in egg, larval, and adult stages upon the leaves of 
clover their presence being indicated by the usual yellowish or rusty blotclies. 



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